The Development Course of Dongfanghong-1 Satellite
1965655438+1On October 8th, Qian Xuesen suggested that China's suspended artificial earth satellite be re-launched and included in the national task, which was approved by Vice Premier Nie. 1965 in may, premier Zhou Enlai instructed China academy of sciences to come up with a specific plan for 1 artificial satellite. Qian Ji, who is in charge of the whole satellite group, led young scientists and technicians to put forward a preliminary plan soon. Qian Ji and others directly reported this plan to Premier Zhou Enlai. 1 In September, 1965, with the progress of launch vehicle technology in China, China Academy of Sciences began to set up a satellite design institute with Zhao Jiuzhang as its president and code-named "65 1" (publicly named as "Scientific Instrument Design Institute"), and named China's1satellite Dongfanghong No.1. Since then, the development of China artificial earth satellite has been officially launched.
From 1965 1 October 20th to 1 1654381October 30th, a demonstration meeting on the overall scheme of China1artificial earth satellite was held, and the Dongfanghong-1 satellite was finally determined as a scientific exploration. The launch time of Dongfanghong-1 is set at 1970, and the general requirement of 1 artificial earth satellite is "to be able to get up, catch, listen and see". The so-called "up" is to ensure that the satellite flies into the sky first; "Catch" means that the ground equipment can measure and control the satellite after it has been on the ground for days; "Audible" means that the satellite wants to broadcast music, which can be received and heard by the ground; "Visible" means that when the satellite is in orbit, people on the ground can see it directly with the naked eye to inspire people.
At the beginning of 1967, the central government officially confirmed that the China 1 artificial earth satellite would play the music of Dongfanghong, so that people all over the world could hear the sound of China satellite. On April 1970, a special train carrying two Dongfanghong-1 satellites and 1 Long March-1 carrier rocket arrived at Jiuquan Satellite Launch Site in China. On the afternoon of April 2, Zhou Enlai heard a report on China's upcoming launch of the/KLOC-0 satellite and its launch vehicle in the Great Hall of the People. In the early morning of April 24th, President Mao Zedong approved the launch.
1 At 2 1 35 on April 24, 1970, China's1artificial earth satellite Dongfanghong-1 was launched by the Long March-1 carrier rocket from Jiuquan Satellite Launch Site in Gansu Province and entered the scheduled orbit at 2 1 48. The specific task of Dongfanghong-1 is to measure the working parameters of the satellite itself; Detecting space environment parameters; It lays a technical foundation for satellite orbit measurement and radio telemetry in China. In order to achieve the above goals and meet these requirements, experts have repeatedly demonstrated that Dongfanghong-1 consists of seven subsystems: Dongfanghong's structure, temperature control, energy, music device and short-wave telemetry, tracking, antenna and attitude measurement.
The instrument cabin on the satellite is equipped with power supply, radar transponder for orbit measurement, radar beacon, telemetry device, electronic tone generator and transmitter, scientific test instruments, etc. Dongfanghong-1 satellite has a diameter of only 1 meter. In order to make the ground "visible", technicians designed the satellite shape as a sphere composed of 72 polyhedrons. One of the purposes is to make the satellite twinkle in orbit. Because the satellite is spin-stable, it will flicker at different angles when rotating, so it is easier to observe on the ground. However, research shows that because the satellite is too small, even so, it can't be seen in bad weather because the brightness of the satellite itself is only about six stars. So, the technicians brainstormed and came up with a new method: changing the "coat" of the three-stage solid rocket from a conical "skirt" to a spherical "main body", and finally turning it into a table with a diameter of 4 meters through the rotating motion of the three-stage solid rocket and observing the stretching motion of the main structure itself. In other words, in order to see the satellite with naked eyes on the earth, an "observation skirt" was added to the upper stage rocket, so that the brightness of the upper stage rocket was increased to 2-3 stars, which was convenient for people to watch. The specific approach is:
Make a big cloth balloon (or "apron") and wrap the three-stage rocket. Don't let go when launching, and blow again the next day, so that it can be stretched to more than 3 meters; At the same time, the cloth balloon is also coated with a layer of aluminum, which reflects sunlight in a large area. In that case, the visual effect is much greater than 1 m, which greatly improves the observation brightness. But what you see with the naked eye is a balloon, or a top-stage rocket with an apron, not the satellite itself. Balloons play a guiding role. After seeing the balloon, because the three-stage rocket and the satellite are in the same orbit, the speed orbit is similar to that of the satellite in tandem, and the distance before and after is not far, so it is easy to find Dongfanghong-1 satellite nearby. On the second day after the launch of Dongfanghong-1, at the request of Premier Zhou Enlai, China predicted the time when Dongfanghong-1 satellite would fly over the capitals of various countries for observation, which aroused strong repercussions from many countries at that time. The satellite is a 72-sided body with a diameter of about 1m and a mass of 1.73kg. Spin attitude stabilization mode is adopted, and the rotation speed is 1.20 rpm. Attitude is determined by solar goniometer and infrared horizon.
Dongfanghong No.1 adopts a nearly spherical 72-face design shape, with the following considerations:
First, it can make satellites have more space for structural utilization; Second, it is more convenient and reliable to stick solar cells on a plane than on a curved surface; Thirdly, because the satellite adopts the spin-stable mode, that is, the orientation of the satellite's spin axis relative to the sun is constantly changing, sticking solar cells on the 72-surface spherical surface can facilitate the uniform distribution of solar cells on different radial surfaces, so that the total output of solar cells does not change much at any time, which is very beneficial to the design of the whole satellite energy system (although the solar cells are not stuck on Dongfanghong-1 eventually due to the changes in satellite tasks and technical schemes, the structural design has not changed). In addition, the design scheme has been successfully applied to Shi Jian-1, China's second artificial satellite, which has the same shape as Dongfanghong-1 and has a service life of more than 8 years. Fourthly, the spherical design can make the ballistic cross section of the satellite basically unchanged when flying, so the atmospheric density and its change at the flying height of the satellite can be inversed and calculated by using the orbit measurement and tracking data of the satellite without installing detection instruments on the satellite, so as to obtain more scientific data. Several schemes have been put forward on how to make the musical sound of Dongfanghong. After comparison, it is decided to adopt electronic music with high reliability, long working life, low power consumption and pleasant and bright music sound. As for how to send the music of Dongfanghong, three schemes have been put forward. Finally, after research, it is decided to use 1 transmitter to send the music of Dongfanghong alternately. However, in order for ordinary radios to directly hear the music of Dongfanghong-1 satellite, it is necessary to install a high-power transmitter on the satellite, but that would make the satellite weigh more than 1 ton, which was not feasible for the carrying capacity of China rockets at that time. Therefore, it is received by large ground stations and then broadcast by radio stations. Therefore, after the launch of the satellite, the music of "Dongfanghong" heard by the people all over the country is satellite signals relayed by radio stations. Designers had planned to spread Mao Zedong's badges all over the Dongfanghong-1 satellite, but at the instruction of Premier Zhou Enlai, these badges were not launched together to reduce the quality of the satellite.
Because it was in the turmoil of the Cultural Revolution, playing Dongfanghong's music was not only a scientific research task, but also a political task with great responsibility. If the satellite goes into the sky and the music changes or stops, this is undoubtedly a major political issue, and developers may be arrested and imprisoned. Under the heavy ideological burden and mental pressure, He, the head of the overall satellite team, and Liu Chengxi, the chief designer of the music installation, took political risks and started their technical exploration, which solved a series of problems such as music disorder and tone sandhi. The music of Dongfanghong is finally produced by electronic circuit, which simulates the sound of aluminum piano. 1968 produced the first batch of prototype products of musical instruments in a factory in Chongqing in the first half of the year. Because the production order was abnormal at that time, many components in the product were welded. Finally, the products of Paradise were re-produced by Shanghai Scientific Instrument Factory.
In order to meet the development requirements of Dongfanghong-1 satellite, technicians adopted many new technologies, such as riveting, anodic electrolytic polishing, large-area gold plating of bright aluminum parts and heat treatment of aluminum parts, and made many innovations in tools and equipment, which provided material guarantee for completing the mission of Dongfanghong-1 satellite.
For example, the anodic electropolishing process of satellite skin is carried out in the open air without a house; Without containers, three large aluminum cans were cast, a hole was dug in the snow, the aluminum cans were placed on them and burned with firewood. The experiment of anodic electrolytic polishing was carried out under such conditions. After hundreds of tests in two months, the skin emissivity and absorption rate finally reached the specified technical indicators.